surshar / claude-code

Claude Code is an agentic coding tool that lives in your terminal, understands your codebase, and helps you code faster by executing routine tasks, explaining complex code, and handling git workflows - all through natural language commands.

Built by Anthropic · github.com/anthropics

claude-code / plugins / plugin-dev / skills / skill-development / references / skill-creator-original.md

Daisy S. HollmanMerge pull request #11780 from anthropics/daisy/plugin-dev/public-marketplace c508e59 · on Nov 18, 2025 History

209 lines · 11.3 KBPreview CodeRaw

1	---
2	name: skill-creator
3	description: Guide for creating effective skills. This skill should be used when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations.
4	license: Complete terms in LICENSE.txt
5	---
6
7	# Skill Creator
8
9	This skill provides guidance for creating effective skills.
10
11	## About Skills
12
13	Skills are modular, self-contained packages that extend Claude's capabilities by providing
14	specialized knowledge, workflows, and tools. Think of them as "onboarding guides" for specific
15	domains or tasks—they transform Claude from a general-purpose agent into a specialized agent
16	equipped with procedural knowledge that no model can fully possess.
17
18	### What Skills Provide
19
20	1. Specialized workflows - Multi-step procedures for specific domains
21	2. Tool integrations - Instructions for working with specific file formats or APIs
22	3. Domain expertise - Company-specific knowledge, schemas, business logic
23	4. Bundled resources - Scripts, references, and assets for complex and repetitive tasks
24
25	### Anatomy of a Skill
26
27	Every skill consists of a required SKILL.md file and optional bundled resources:
28
29	```
30	skill-name/
31	├── SKILL.md (required)
32	│ ├── YAML frontmatter metadata (required)
33	│ │ ├── name: (required)
34	│ │ └── description: (required)
35	│ └── Markdown instructions (required)
36	└── Bundled Resources (optional)
37	├── scripts/ - Executable code (Python/Bash/etc.)
38	├── references/ - Documentation intended to be loaded into context as needed
39	└── assets/ - Files used in output (templates, icons, fonts, etc.)
40	```
41
42	#### SKILL.md (required)
43
44	Metadata Quality: The `name` and `description` in YAML frontmatter determine when Claude will use the skill. Be specific about what the skill does and when to use it. Use the third-person (e.g. "This skill should be used when..." instead of "Use this skill when...").
45
46	#### Bundled Resources (optional)
47
48	##### Scripts (`scripts/`)
49
50	Executable code (Python/Bash/etc.) for tasks that require deterministic reliability or are repeatedly rewritten.
51
52	- When to include: When the same code is being rewritten repeatedly or deterministic reliability is needed
53	- Example: `scripts/rotate_pdf.py` for PDF rotation tasks
54	- Benefits: Token efficient, deterministic, may be executed without loading into context
55	- Note: Scripts may still need to be read by Claude for patching or environment-specific adjustments
56
57	##### References (`references/`)
58
59	Documentation and reference material intended to be loaded as needed into context to inform Claude's process and thinking.
60
61	- When to include: For documentation that Claude should reference while working
62	- Examples: `references/finance.md` for financial schemas, `references/mnda.md` for company NDA template, `references/policies.md` for company policies, `references/api_docs.md` for API specifications
63	- Use cases: Database schemas, API documentation, domain knowledge, company policies, detailed workflow guides
64	- Benefits: Keeps SKILL.md lean, loaded only when Claude determines it's needed
65	- Best practice: If files are large (>10k words), include grep search patterns in SKILL.md
66	- Avoid duplication: Information should live in either SKILL.md or references files, not both. Prefer references files for detailed information unless it's truly core to the skill—this keeps SKILL.md lean while making information discoverable without hogging the context window. Keep only essential procedural instructions and workflow guidance in SKILL.md; move detailed reference material, schemas, and examples to references files.
67
68	##### Assets (`assets/`)
69
70	Files not intended to be loaded into context, but rather used within the output Claude produces.
71
72	- When to include: When the skill needs files that will be used in the final output
73	- Examples: `assets/logo.png` for brand assets, `assets/slides.pptx` for PowerPoint templates, `assets/frontend-template/` for HTML/React boilerplate, `assets/font.ttf` for typography
74	- Use cases: Templates, images, icons, boilerplate code, fonts, sample documents that get copied or modified
75	- Benefits: Separates output resources from documentation, enables Claude to use files without loading them into context
76
77	### Progressive Disclosure Design Principle
78
79	Skills use a three-level loading system to manage context efficiently:
80
81	1. Metadata (name + description) - Always in context (~100 words)
82	2. SKILL.md body - When skill triggers (<5k words)
83	3. Bundled resources - As needed by Claude (Unlimited*)
84
85	*Unlimited because scripts can be executed without reading into context window.
86
87	## Skill Creation Process
88
89	To create a skill, follow the "Skill Creation Process" in order, skipping steps only if there is a clear reason why they are not applicable.
90
91	### Step 1: Understanding the Skill with Concrete Examples
92
93	Skip this step only when the skill's usage patterns are already clearly understood. It remains valuable even when working with an existing skill.
94
95	To create an effective skill, clearly understand concrete examples of how the skill will be used. This understanding can come from either direct user examples or generated examples that are validated with user feedback.
96
97	For example, when building an image-editor skill, relevant questions include:
98
99	- "What functionality should the image-editor skill support? Editing, rotating, anything else?"
100	- "Can you give some examples of how this skill would be used?"
101	- "I can imagine users asking for things like 'Remove the red-eye from this image' or 'Rotate this image'. Are there other ways you imagine this skill being used?"
102	- "What would a user say that should trigger this skill?"
103
104	To avoid overwhelming users, avoid asking too many questions in a single message. Start with the most important questions and follow up as needed for better effectiveness.
105
106	Conclude this step when there is a clear sense of the functionality the skill should support.
107
108	### Step 2: Planning the Reusable Skill Contents
109
110	To turn concrete examples into an effective skill, analyze each example by:
111
112	1. Considering how to execute on the example from scratch
113	2. Identifying what scripts, references, and assets would be helpful when executing these workflows repeatedly
114
115	Example: When building a `pdf-editor` skill to handle queries like "Help me rotate this PDF," the analysis shows:
116
117	1. Rotating a PDF requires re-writing the same code each time
118	2. A `scripts/rotate_pdf.py` script would be helpful to store in the skill
119
120	Example: When designing a `frontend-webapp-builder` skill for queries like "Build me a todo app" or "Build me a dashboard to track my steps," the analysis shows:
121
122	1. Writing a frontend webapp requires the same boilerplate HTML/React each time
123	2. An `assets/hello-world/` template containing the boilerplate HTML/React project files would be helpful to store in the skill
124
125	Example: When building a `big-query` skill to handle queries like "How many users have logged in today?" the analysis shows:
126
127	1. Querying BigQuery requires re-discovering the table schemas and relationships each time
128	2. A `references/schema.md` file documenting the table schemas would be helpful to store in the skill
129
130	To establish the skill's contents, analyze each concrete example to create a list of the reusable resources to include: scripts, references, and assets.
131
132	### Step 3: Initializing the Skill
133
134	At this point, it is time to actually create the skill.
135
136	Skip this step only if the skill being developed already exists, and iteration or packaging is needed. In this case, continue to the next step.
137
138	When creating a new skill from scratch, always run the `init_skill.py` script. The script conveniently generates a new template skill directory that automatically includes everything a skill requires, making the skill creation process much more efficient and reliable.
139
140	Usage:
141
142	```bash
143	scripts/init_skill.py <skill-name> --path <output-directory>
144	```
145
146	The script:
147
148	- Creates the skill directory at the specified path
149	- Generates a SKILL.md template with proper frontmatter and TODO placeholders
150	- Creates example resource directories: `scripts/`, `references/`, and `assets/`
151	- Adds example files in each directory that can be customized or deleted
152
153	After initialization, customize or remove the generated SKILL.md and example files as needed.
154
155	### Step 4: Edit the Skill
156
157	When editing the (newly-generated or existing) skill, remember that the skill is being created for another instance of Claude to use. Focus on including information that would be beneficial and non-obvious to Claude. Consider what procedural knowledge, domain-specific details, or reusable assets would help another Claude instance execute these tasks more effectively.
158
159	#### Start with Reusable Skill Contents
160
161	To begin implementation, start with the reusable resources identified above: `scripts/`, `references/`, and `assets/` files. Note that this step may require user input. For example, when implementing a `brand-guidelines` skill, the user may need to provide brand assets or templates to store in `assets/`, or documentation to store in `references/`.
162
163	Also, delete any example files and directories not needed for the skill. The initialization script creates example files in `scripts/`, `references/`, and `assets/` to demonstrate structure, but most skills won't need all of them.
164
165	#### Update SKILL.md
166
167	Writing Style: Write the entire skill using imperative/infinitive form (verb-first instructions), not second person. Use objective, instructional language (e.g., "To accomplish X, do Y" rather than "You should do X" or "If you need to do X"). This maintains consistency and clarity for AI consumption.
168
169	To complete SKILL.md, answer the following questions:
170
171	1. What is the purpose of the skill, in a few sentences?
172	2. When should the skill be used?
173	3. In practice, how should Claude use the skill? All reusable skill contents developed above should be referenced so that Claude knows how to use them.
174
175	### Step 5: Packaging a Skill
176
177	Once the skill is ready, it should be packaged into a distributable zip file that gets shared with the user. The packaging process automatically validates the skill first to ensure it meets all requirements:
178
179	```bash
180	scripts/package_skill.py <path/to/skill-folder>
181	```
182
183	Optional output directory specification:
184
185	```bash
186	scripts/package_skill.py <path/to/skill-folder> ./dist
187	```
188
189	The packaging script will:
190
191	1. Validate the skill automatically, checking:
192	- YAML frontmatter format and required fields
193	- Skill naming conventions and directory structure
194	- Description completeness and quality
195	- File organization and resource references
196
197	2. Package the skill if validation passes, creating a zip file named after the skill (e.g., `my-skill.zip`) that includes all files and maintains the proper directory structure for distribution.
198
199	If validation fails, the script will report the errors and exit without creating a package. Fix any validation errors and run the packaging command again.
200
201	### Step 6: Iterate
202
203	After testing the skill, users may request improvements. Often this happens right after using the skill, with fresh context of how the skill performed.
204
205	Iteration workflow:
206	1. Use the skill on real tasks
207	2. Notice struggles or inefficiencies
208	3. Identify how SKILL.md or bundled resources should be updated
209	4. Implement changes and test again